មេរៀនរងទី 1Key show operational commands ដើម្បី verify VLANs និង switching state (show interfaces terse, show vlans ឬ show bridge domain) និង expected outputsពណ៌នា essential show commands ដើម្បី verify VLANs និង switching state រួមទាំង interface summaries, VLAN membership, និង bridge domains។ ពន្យល់ពីរបៀប confirm tagging, access ports, និង forwarding behavior ប្រឆាំងនឹង design requirements។
Use show interfaces terse for link and VLAN statusCheck VLAN membership with show vlans detailValidate bridge-domain configuration and floodingConfirm access versus trunk port assignmentsCorrelate MAC learning with VLAN forwardingមេរៀនរងទី 2OSPF verification commands (show ospf neighbor, show ospf interface, show route protocol ospf) និង expected resultsគ្របដណ្តប់ OSPF verification commands នៅលើ Junos និងរបៀប interpret outputs របស់ពួកវា។ អ្នកនឹងរៀន confirm neighbor states, interface parameters, LSAs, និង OSPF routes ដើម្បីធានា IGP ផ្គូផ្គងនឹង intended design និង policies។
Interpret show ospf neighbor state transitionsReview show ospf interface cost and timersAnalyze show ospf database and LSA typesValidate OSPF routes with show route protocol ospfCheck area design, stub flags, and summarizationមេរៀនរងទី 3Troubleshooting LAG issues៖ mismatched LACP settings, hashing, និង VLAN membership differencesគ្របដណ្តប់ systematic troubleshooting នៃ LAG incidents នៅលើ Junos ផ្តោតលើ LACP mode និង timer mismatches, hashing configuration, VLAN membership alignment, និងរបៀប recognize symptoms ដូចជា uneven traffic, flaps, ឬ one-way connectivity។
Identify LACP active, passive, and disabled modesCheck LACP system ID, priority, and key valuesVerify hashing algorithms and load-balancing behaviorValidate VLAN tagging and access/trunk alignmentUse logs and counters to detect LAG flapsមេរៀនរងទី 4Common failures និង quick diagnostic checks សម្រាប់ production handoffសង្ខេប frequent production failures និង quick diagnostic steps មុន handoff។ Emphasizes structured checks សម្រាប់ cabling, VLANs, LAGs, STP, និង routing, plus documenting findings ដើម្បី operations teams អាច maintain stability។
Perform initial physical and link-layer checksVerify VLAN, LAG, and STP consistency end to endConfirm routing reachability and default gatewaysCheck logs for recurring errors and flapping eventsDocument baseline state and remediation stepsមេរៀនរងទី 5Commands ដើម្បី validate LAG/ae status និង LACP (show interfaces aeX extensive, show lacp interfaces) និង interpretationលម្អិត operational commands ដើម្បី confirm LAG និង LACP health រួមទាំង interface status, partner information, និង statistics។ ពន្យល់ពីរបៀប interpret key fields នៅក្នុង show outputs ដើម្បី distinguish configuration errors ពី physical ឬ peer issues។
Use show interfaces aeX terse and extensiveInterpret LACP actor and partner state flagsReview LAG member link status and bundle healthAnalyze LACP statistics and timeout behaviorCorrelate LAG status with physical interface logsមេរៀនរងទី 6Layer-2 និង Layer-3 packet-trace និង capture tools នៅលើ Junos (monitor traffic interface, show ethernet-switching table) សម្រាប់ fault isolationពន្យល់ពីរបៀបប្រើ Junos packet-trace និង capture tools នៅ Layer 2 និង Layer 3 ដើម្បី isolate faults។ ផ្តោតលើ monitor traffic, filter usage, និង reading ethernet-switching tables ដើម្បី confirm MAC learning, VLAN forwarding, និង routing behavior។
Run monitor traffic with safe filters appliedCapture and inspect VLAN tags and MAC addressesCorrelate packet captures with ethernet-switching tableTrace routed traffic paths and next-hop resolutionExport captures for offline analysis in Wiresharkមេរៀនរងទី 7Step-by-step troubleshooting flow សម្រាប់ OSPF neighbors not forming៖ physical/link checks, VLAN tagging verification, MTU/hello timer mismatch check, authentication និង interface-type checksផ្តល់ structured troubleshooting flow នៅពេល OSPF neighbors fail ដើម្បី form។ Walks through physical checks, VLAN និង tagging validation, MTU និង timers, authentication, និង interface type mismatches ដើម្បី quickly isolate root cause។
Verify physical links, optics, and interface statusConfirm VLAN tagging and subinterface alignmentCheck MTU, hello, and dead timer consistencyValidate authentication keys and encryption typesReview network type, DR election, and passive flagsមេរៀនរងទី 8Interpreting spanning-tree outputs និង resolving blocking/forwarding state issuesបង្រៀនពីរបៀប interpret spanning-tree outputs នៅលើ Junos កំណត់ root bridge និង port roles និង resolve blocking ឬ forwarding anomalies។ Emphasizes loop prevention, topology changes, និង verifying STP, RSTP, ឬ MSTP parameters។
Identify STP root bridge and path cost valuesDetermine port roles and port states on switchesInvestigate unexpected blocking or forwarding portsCheck BPDU reception, timers, and STP versionsResolve topology changes and flapping STP portsមេរៀនរងទី 9Debug និង log commands សមស្របនឹង OSPF និង LACP (show log messages, monitor traffic, ឬ request support information) និង safe usage guidanceផ្តោតលើ debug និង logging tools សម្រាប់ OSPF និង LACP រួមទាំង show log, monitor traffic, និង request support information។ គ្របដណ្តប់ enabling detailed logs safely, collecting evidence, និង avoiding excessive impact លើ production devices។
Review relevant system and protocol log filesEnable OSPF and LACP traceoptions safelyUse monitor traffic for targeted control-plane captureCollect request support information for TACApply log filters to limit performance impact